Wairoa Wastewater Scheme Presbyterian Methodist Hall, 28 November 2017
What should Wairoa do with its wastewater?
The Journey so far
VIS ISION 1) long-term goal is removing wastewater discharges from the Wairoa River 2) commitment to improving river health not just related to wastewater – but in a holistic way Includes • implementing improvements for managing wastewater, • and improving catchment water quality.
THE STARTING POINT Reconsenting treated Current system not wastewater discharges from considered acceptable by Wairoa District Council’s many - despite not having current wastewater treatment any significant measurable plant needs reconsenting – effects need to consider alternatives Exact effects and impact likely The community would like to being masked condition of see water quality in their the river as a whole river improved.
THE IN INTENT Cultural aspirations and community desires Affordable solution ‘Quick wins’ possible in the short term • improving effluent quality • irrigating land close to the wastewater treatment plant
THE PACKAGE - INTENTION IN Better River discharge treatment Develop land Better Sewer discharge wastewater improvements options over management time Improved river health Administrative support Better catchment management
THE PACKAGE - OVERVIEW Now A - Soon B - Interim C - Future • 100 % River • Sand filter • As with Soon, • As much as discharge system but more and possible applied larger irrigation to land • UV treatment areas before river • Possibly only discharge • Investigate and when significant construct some storms there is • Look at some storage ponds discharge to river land application (irrigation)
THE PACKAGE DETAILS Wastewater Wastewater Catchment Infrastructure Irrigation Advocacy Improvements • Extra treatment • Irrigate neighbouring land • Contribute to driving catchment improvements • Filtration - sand/media to remove algae and • Adjacent land particulate • WDC to be part of catchment decisions • Potentially council land includng Landfill • Disinfection - Ultra Violet Light Treatment to forestry • Work with HBRC and community to reduce bugs even further than curent • Other farmers in area as needed make changes treatment • Provide some storage to reduce summer • Work with community to create • Reticulation upgrades river discharge opportunities • Sewer pipe replacement • Develop over time based on willingness • Partial funding of catchment • Pump station upgrades and funding administration • Discharge management • Ceasing illegal connections • Add storage to allow for continuous slower dicharge rate • Maintain existing discharge • Make upgrades • Change to 24/7 discharge • Make changes over time
THE OPTIONS Many and varied Many are technically challenged Many too expensive for the community Include • continuing the existing discharge, • modifying the existing discharge potentially with additional treatment, • using an ocean outfall and • various forms of land application.
CONSIDERATIONS Need to balance • level of investment required – Parts A, B or C • potential improvements and benefits from investing Need to decide on • minimum level of treatment • costs • whether investment is proportionate to the improvement in Wairoa River i.e. better gains with money spent elsewhere Remember • wastewater management is a modern phenomenon that largely didn’t exist 100 years ago ,
OTHER CONSIDERATIONS Manage unique wastes • commercial wastes • mortuary waste and • hospital waste Reticulation improvements • reduce stormwater and groundwater entering the system • pump station capacity improvements
IM IMPLICATIONS • Costs to be affordable to rate payers ($5 Financial million project = $200/yr or $4/wk rate increase over 30 years) - Part A • Inclusion of land for filtration and ideally no Cultural wastewater going directly into river • Improved bug removal and ideally minimal Environmental wastewater going to water • Limited wastewater entering water and Recreational improved bug removal
TIM IMING Within 5 Years Within 10 years Within 20 years Within 30 years • Improvement of areas • Expand wastewater • Further irrigation areas • Removal of all (or of the reticulation irrigation area to WDC identified and most) wastewater system (i.e. pipe forestry block (landfill infrastructure put in discharge to the river relining) area) and neighbouring place (i.e. up to 300 ha • Further irrigation areas land of irrigation) • Improve treatment of identified (i.e. up to effluent discharging • Continue reticulation • Catchment project 600 ha of irrigation) from the WWTP to the improvements works have covered • Up to 70% of the estuary, allowing for 24 50% of the catchment • Develop storage catchment area has hour discharge area capacity to make had project works • Add an area of treatment more established and irrigation (<50 ha) close effective and irrigation maintenance of these to treatment ponds options more viable areas will be ongoing • WDC to advocate for • Catchment projects Wairoa River underway (i.e. riparian Catchment initiatives planting and retirement of grazing land in priority sub- catchments)
COSTS Gradual implementation over time starting with additional treatment; Part A - target $5 million or about $200 per connection per year ($4/wk) If additional funding could do more – Parts B and C
FIN INAL NOTE it has taken more than 100 fixing it will not happen years for the river to reach overnight its current condition
THE PACKAGE - SUMMARY Now A - Soon B - Interim C - Future • 100 % River • Sand filter • As with Soon, • As much as discharge system but more and possible applied larger irrigation to land • UV treatment areas before river • Possibly only discharge • Investigate and when significant construct some storms there is • Look at some storage ponds discharge to river land application (irrigation)
NEXT What do you think? What is What is Why is it right What is right good? Wrong? or wrong?
FEEDBACK When • On going • Good to have some by 8 December • Council meeting to discuss 13 December • Recommendation to Council early Feb 2018 How • Now • Next couple days • Email • Web • Phone
End • Extra slides follow
THE SOLUTION Long term sustainable wastewater solution • requires multiple angles to be considered to improve river health • opportunities exist and are needed to improve the Mauri of the Wairoa River Both objectives can work alongside each other, and potentially can be complementary when addressed as a Package .
SU SUMMARY – IN INVESTIGATIONS & TECHNICAL INFORMATION IN A range of technical reports have been completed summarising background information. These relate to various areas of the wastewater system, the environment and the management of such a system. These reports assist with developing options along with engagement with the community and affected parties. Tangata Reticulation Treatment Water Land Planning Whenua • Wastewater • Analysis of • River • Land • Identification • Policy flows and current monitoring and assessment of sites of documentation modelling treatment and assessment of and costs for significance identified – investigated flows entering water quality wastewater and worldview Freshwater and the wastewater around the irrigation on Wairoa Coastal and treatment outfall pipe suitability wastewater Options for ponds around Wairoa wastewater identified Please visit the Wairoa District Council Website for further information http://www.wairoadc.govt.nz/services/water/wastewater/
SUMMARY – OPTIONS & COSTS Status Quo < $2 M • 1.1 Status Quo • 1.2 River-low bugs/24-hour continuous discharge River • 2.1 River-low bugs • 2.2 River-low bugs/HRLP-OLF $2 - 5 M • 2.3 River-HRLP-OLF • 2.4 River-50% flow/low bugs/HRLP-OLF • 2.5 River(new)-low bugs -HRLP-OLF Ocean $15 - 20 M • 3.1 Ocean • 3.2 Ocean-HRLP-OLF Land • 4.1 Land-90 day storage buffer/irrigation rate 1 Rule of thumb: • 4.2 Land-120 day storage buffer/irrigation rate 1 • 4.3 Land-50% flow/90 day storage buffer/irrigation rate 1 • 4.4 Land-50% flow/120 day storage buffer/irrigation rate 1 > $20 M $5 M = $200/y = $4/wk • 4.5 Land-90 day storage buffer/irrigation rate 2 • 4.6 Land-120 day storage buffer/irrigation rate 2 • 4.7 Land-50% flow/90 day storage buffer/irrigation rate 2 • 4.8 Land-50% flow/120 day storage buffer/irrigation rate 2 $10 M = $400/y = $8/wk • 4.9 Land-rapid infiltration Combo $10 < 20 M • 5.1 Combo-River/land-HRLP-OLF/14 day storage buffer • 5.2 Combo-River/land-HRLP-OLF/90 day storage buffer • 5.3 Combo-50% flow/River/land-HRLP-OLF/14 day storage buffer • 5.4 Combo-50% flow/River/land-HRLP-OLF/90 day storage buffer
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